I'd give odds that it is the K1.

Will a dealer do a K1 or yank the whole thing and bill DC for a rebuild job? The latter gives the mechanic more opportunity to forget a screw or torque something wrong, etc.

Warranty or no, I wouldn't care to have something "rebuilt" that wasn't broken.

My local dealer's brand new $10mm facility wasn't built by doing the least expensive fix first.

Kevin